refactor(estree/tokens): reduce repeated code

[overlookmotel]

Pure refactor. Move code for converting a span from UTF-8 to UTF-16 into its own function, instead of having the same code in 3 places.

[overlookmotel]

• feat(estree/tokens): add function to update tokens in place #19856 : 2 dependent PRs (#19858 , #19865 )
• refactor(estree/tokens): reduce repeated code #19857 👈 (View in Graphite)
• ci(benchmarks): add benchmark for updating tokens for raw transfer #19854
• feat(parser): add mutate_tokens Cargo feature #19853
• refactor(parser): Token::set_* method visible only within lexer #19852
• perf(estree/tokens): preallocate sufficient space for tokens JSON #19851
• refactor(estree/tokens): break up into multiple files #19850
• perf(estree/tokens): introduce ESTreeTokenConfig trait #19842
• refactor(estree/tokens): move logic for JSX identifiers into JSXState struct #19839
• fix(linter/plugins): decode escapes in identifier tokens #19838
• refactor(estree/tokens): re-order code #19837
• docs(estree/tokens): improve comments #19836
• refactor(estree/tokens): make ESTreeUnsafeToken type private #19835
• refactor(estree/tokens): rename types #19834
• fix(estree/tokens): convert this tokens in TSTypeName #19815
• perf(estree/tokens): do not JSON-encode keyword, punctuator, etc tokens #19814
• perf(estree/tokens): do not JSON-encode this identifiers #19813
• perf(estree/tokens): do not JSON-encode JSX identifiers #19812
• perf(estree/tokens): handle regex tokens separately #19796
• perf(estree/tokens): use strings from AST for identifier tokens #19744 : 1 other dependent PR (#19735 )
• refactor(estree/tokens): add TokenType type #19789
• feat(estree): add IS_COMPACT const to Formatter trait #19787
• feat(estree): expose buffer and formatter of serializers #19773
• perf(estree): use CodeBuffer::print_strs_array to reduce bounds checks #19766
• feat(data_structures): add CodeBuffer::print_strs_array #19760
• perf(estree): use CodeBuffer::print_indent #19727
• perf(estree/tokens): serialize tokens while visiting AST #19726
• perf(estree/tokens): serialize with ESTree not serde #19725
• feat(estree): oxc_estree crate export config and formatter types #19724
• refactor(estree/tokens): convert tokens spans before AST spans #19723
• refactor(estree/tokens): simplify code #19722
• perf(estree/tokens): do not branch on presence of override twice #19721
• refactor(estree/tokens): move logic for excluding legacy identifiers into visitor #19720
• perf(estree/tokens): replace hash map with Vec #19718
• perf(estree/tokens): replace multiple hash sets into a single hash map #19716
• refactor(estree/tokens): replace stored token when re-lexing #19698
• perf(parser): remove branches from finish_next_inner #19695
• perf(parser): remove const generic param from finish_next_inner #19684
• feat(parser): add LexerConfig::TOKENS_METHOD_IS_STATIC const #19683
• docs(parser): improve doc comments for ParserConfig and LexerConfig #19682
• refactor(estree/tokens): use wildcard import for AST types #19681
• test(estree): ESTree conformance check files with hashbangs #19680
• fix(estree/tokens): reverse field order of regex object in tokens #19679
• perf(estree/tokens): serialize tokens to compact JSON #19572
• ci(benchmarks): correct comment #19650
• perf(parser/tokens): pre-allocate capacity for tokens #19543
• fix(estree/tokens): generate tokens for files with BOM #19535
• refactor(estree/tokens): combine collect_token_context into to_estree_tokens_json #19534
• refactor(estree): reorder tokens code #19533
• refactor(coverage): standardize ESTree tokens testing functions #19532
• perf(linter/plugins): remove typescript from bundle #19531
• docs(linter/plugins): correct doc comments for initTokens #19530
• refactor(linter/plugins): combine functions for getting tokens #19529
• ci(benchmarks): benchmark parser with tokens and ESTree tokens conversion #19649
• perf(linter/plugins): use Oxc tokens in plugins #19498
• test(estree/tokens): do not skip tokens conformance tests for files with hashbangs #19643
• fix(estree): fix tokens for JSX #19524
• perf(parser): introduce ParserConfig #19637
• feat(parser,estree,coverage): collect tokens in parser and convert to ESTree format #19497
• feat(coverage): add estree token conformance scaffolding #19496
• fix(tasks/coverage): bring back acorn-jsx estree testing #19516 : 1 other dependent PR (#19515 )
• chore(submodules): update submodule SHAs to latest commits #19518
• main

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[codspeed-hq]

Merging this PR will not alter performance

✅ 53 untouched benchmarks
⏩ 3 skipped benchmarks¹

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_{Comparing om/02-28-refactor_estree_tokens_reduce_repeated_code (f4a1906) with om/02-24-ci_benchmarks_add_benchmark_for_updating_tokens_for_raw_transfer (efbb82b)}

Footnotes

1. 3 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[Copilot]

Pull request overview

Refactors ESTree token serialization to centralize UTF-8 → UTF-16 span conversion logic, reducing duplication while preserving existing serialization behavior.

Changes:

• Extracted repeated span conversion logic into a new get_utf16_span helper.
• Updated safe/unsafe token serialization paths and RegExp token serialization to use the helper.
• Clarified advance_to behavior via an additional doc comment.

[overlookmotel]

Merge activity

• Mar 1, 8:03 AM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Mar 1, 8:04 AM UTC: overlookmotel added this pull request to the Graphite merge queue.
• Mar 1, 8:12 AM UTC: Merged by the Graphite merge queue.